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v3.20.4

Credit Facilities, Long-Term Debt and Lease Liabilities - Restrictions on Non-Recourse Debt and Security (Details) $ in Millions, $ in Millions |  | 12 Months Ended
--- | --- | ---
Jul. 20, 2018 CAD ($) | Dec. 31, 2020 CAD ($) | Dec. 31, 2020 AUD ($) | Dec. 31, 2019 CAD ($) | Dec. 31, 2018 CAD ($)
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Other borrowings |  | $ 730 |  | $ 326 |
PP&E |  | 5,822 |  | 6,207 | $ 6,164
Intangible assets |  | 313 |  | 318 | 373
Alberta Off-Coal Agreement | $ 40 | 40 |  | 40 | $ 40
Alberta off-coal agreement, annual cash payments, net | $ 37 |  |  |  |
US Wind Projects - Big Level |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Restricted cash (Note 22) |  | 9 |  | 15 |
TransAlta OCP |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Restricted cash (Note 22) |  | 17 |  | 17 |
TEC |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Restricted cash (Note 22) |  | 45 |  | 0 |
Renewable generation facilities |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
PP&E |  | 1,277 |  | 967 |
Intangible assets |  | 88 |  | 63 |
Non-recourse debt |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Other borrowings |  | 1,800 |  | 1,100 |
Restricted cash (Note 22) |  | 73 |  | 42 |
Non-recourse debt | Secured by first rate ranking charge over subsidiaries |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Notional amount |  | 1,441 |  | 719 |
Non-recourse debt | Secured by equity interests of the issuer |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Notional amount |  | 111 |  | 119 |
Restricted Use Debt |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Proceeds from issue of bonds, notes and debentures |  |  | $ 7 |  |
Secured Debt | TransAlta OCP |  |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |  |
Notional amount |  | $ 285 |  | $ 305 |

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